


Perfect Harmony

by astudyinfic



Series: Flash Bang #1 (Indigo Team) [2]
Category: Shadowhunters (TV)
Genre: M/M, Meet-Cute, cellist Alec, mundane AU, musician au, pianist magnus, unending fluff
Language: English
Status: Completed
Published: 2018-04-19
Updated: 2018-04-19
Packaged: 2019-04-24 22:26:14
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,131
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14364981
Author URL: https://archiveofourown.org/users/astudyinfic/pseuds/astudyinfic
Summary: As a pianist, Magnus has never been quite so dedicated to practicing as he has been as of late.  It might have something to do with his new apartment.  But most likely it is to do with the cellist who plays with him every day, despite the fact that Magnus has never seen their face.But if the music is to be believed, that cellist might be the most beautiful person in the world.Square #18: Musician AU





	Perfect Harmony

**Author's Note:**

> For the Shadowhunters Hiatus Flash Bang #1

After more than twenty years of playing the piano, Magnus had never been quite so dedicated to his practice.  He could say it was because he now had his own place, no longer bothering roommates with his playing. But none of his roommates ever complained and some even requested him to play for them. So, no, he couldn’t blame the quiet atmosphere of his own home for his sudden enjoyment of practice.  

He could say it was the presence of the baby grand that took up most of his living room, its very existence encouraging him to play more, to put down the martini and put his fingers to the keys instead.  But he’d had pianos around all his life, ever since he showed a talent for the instrument. Just because he had one around didn’t mean he would practice. So that wasn’t it either.

No, Magnus knew exactly why he was practicing more and it had everything to do with the man living directly across from his living room window.  Not that he knew that at the time.  

It didn’t start out like that.  When he moved in, the piano was the first thing he set up, sitting down to play through one of his favorite pieces, _Clair de Lune_.  It was the first piece he performed in public, the first one ever requested by someone, the piece that won over his now ex-girlfriend who moved to Los Angeles but still held a place in his heart.  In short, a piece that meant so very much to him.

Closing his eyes, his hands danced over the keys, pulling the beloved music from his instrument without thought, only emotion.  It flowed over him and out the open windows of his apartment, contrasting beautifully with the chaotic din of the city below.

As he reached the second time through the main melody, he paused briefly, confused as a new voice entered the tune.  The same song, in the same key, but a very different sound, working in perfect harmony with his own. Magnus continued to play, straining to hear the added the added part.  Eventually, his fingers stopped moving and he just listened as the other faded slowly away. It was coming from outside, he knew that much but by the time he got to the window, the music and the musician were nowhere to be seen.  Magnus chalked it up to a strange coincidence and went back to unpacking his belongings.

The following week, Magnus couldn’t get the haunting melody out of his head.  He’d heard the song so many times on piano he could no longer count, but that other instrument added a dimension he’d never heard before.  But not knowing who played it and not having heard it long enough to figure out what the instrument was, Magnus was at a loss. For eight days, he heard nothing from the mysterious musician, until one afternoon when he was home sick with a cold, the music started once more.  

This time, Magnus recognized the instrument almost instantly.  Even if the song weren’t one of the most famous pieces of music for the cello ever, the soulful sound gave it away.  Magnus loved the instrument and listened to it through the entire work, _The Swan_ being so peaceful and relaxing that he nearly fell asleep to the dulcet tones coming through his open window.  He probably would have drifted off with images of a beautiful yet mysterious cellist in his mind if the song hadn’t come to an end and _Clair de Lune_ started a moment later.  

Despite feeling ill, Magnus couldn’t help but push himself out of his blanket cocoon and open his piano.  It took a minute but soon he started to play, fingers following the familiar melody as he took all his cues from the person playing the cello.  They played through it a number of times and each time Magnus marveled at how much emotion the person behind the other instrument could put into such a simple and famous song.  Each time through conveyed a different sense of being to the point that it hardly felt like _Clair de Lune_ at all, but rather a conversation between the two musicians.  

When they reached the end and the other did not start it once more, Magnus waited to see if the cellist picked up another song.  They did not and Magnus considered only briefly before starting in on Brahms’s Cello Suite No. 1, one of the few cello pieces he knew by heart.  It took literal seconds before the other joined in. The music ebbed and flowed, filling his home with the most beautiful sounds he’d ever heard.

By the time the two of them had reached the end, Magnus’ cold forced him away from the bench and back onto the couch to sleep.  But this time, he really did dream of his mysterious duet partner and their magical fingers.

Over the following month, the two met at least once a week to play.  Magnus learned that the other was a fan of the classics and it felt like the cellist put his heart and soul into every piece they played.  Each song made him think he knew the musician just a little better. While he was terribly curious to find this person, to see if the beauty of their music was matched on their face, there was something romantic about creating music with someone you could neither see nor touch.  

“I bet they are beautiful,” Magnus sighed onto the phone one day, his window open as he kept one ear out for the telltale notes from a cello, even while he spoke with Ragnor.  “No one could create that kind of music and not be as beautiful on the outside.”

It had become a common topic of conversation for them.  Magnus’ curiosity was reaching a fever pitch and Ragnor, as both his best friend and fellow music enthusiast was the one who had to listen to his drama.  “I have seen enough seasons of the London Philharmonic to prove you wrong, Magnus,” Ragnor sighed and Magnus could almost see him rolling his eyes, despite the fact that they were an ocean apart.

He ignored his friend’s cynicism and continued, “No, definitely beautiful, with dextrous fingers and a gorgeous instrument between their thighs.  Honestly, I’m jealous of the instrument. Why should it get all the love when I am here and available?”

“The person is probably in their eighties and married for more than half their life.  Give it up, Magnus.”

“I will not give up.  There’s something there and I will prove it.”  As he spoke, he heard the music start up outside and he grinned.  “And there is my muse now.” But before he could even sign off the call, a harmony joined in.  A piano. And not played by Magnus. “Ragnor,” he hissed, “They’re cheating on me. I have to go.”

He didn’t wait for Ragnor to reply, disconnecting and rushing to the window to see where the music was coming from.  It was definitely his cellist, he’d know that music anywhere, even if it was nothing they’d played together. Was that...pop music?  Magnus frowned, staring out the window until he found the other open one, directly across from him. Gauzy curtains were drawn but they fluttered in the breeze.  He sat there, staring at the window, trying to catch a glimpse of the person playing (and whoever they had the audacity to play with on the piano).

A blond man sat at the piano, hunched in concentration as he played the song.  He was good, not nearly as expressive as either Magnus or his cellist but technically excellent.  But who Magnus really wanted to see was seated so he could only catch the smallest sight of him. He was definitely a man, tall if the way his legs were bent was to be believed.  Dark hair. And that was all he could tell. Magnus had half a mind to go over there and demand to know who the pianist was and why his cellist would play with him, but they’d never spoken, they didn’t know each other.  Magnus had no right to his jealousy. He had no claim on the man.

He listened to them transition to a different pop song before slamming the window shut.  He didn’t need to hear that. And when he heard the man play the next day, all on his own, he slammed the window shut again.  It was ridiculous and he knew it. But that didn’t stop him.

The third day, however, he couldn’t hold back when he heard the familiar tune drift through his window.  Instead of closing it, he went to his piano and played, leading the tune this time instead of following the cellist’s lead.  He poured all his anger, his annoyance, and his jealousy into the notes as his fingers danced across the keys. As he played, his anger shifted to something sadder and slower.  

Loneliness.  

Magnus wanted to know the man who could play such beautiful music.  He wanted to hear his hopes and dreams, find out where he learned to play and why he continued to do so.  He wanted the happiness their music gave him but he wanted it with the man there. The cellist stopped playing and Magnus followed suit a moment later.  With a deep breath, he took a chance and walked over to the window, looking to the apartment where he knew the man lived.

His bravery was rewarded with the most beautiful face he’d ever seen.  The man had warm eyes - brown or green or hazel he couldn’t tell from this distance - and hair that looked like he just got out of bed (wouldn’t Magnus love to be the cause of that).  The way he bent over was similar to Magnus so they had to be about the same height. And that smile, warm and gracious and slightly shy, turned Magnus’ insides to jelly and sent his heart into overdrive.  The man smiled once more and blushed brilliantly when Magnus winked in return. They closed their windows and returned to their lives, a smile gracing Magnus’ lips for the rest of the night.

Over the time they’d been playing together, Magnus noticed a pattern.  The cellist always played in the afternoon, never very early or late. And while Magnus loved their routine, he wanted to switch things up just a little.  

So that morning, he got a piece of paper and wrote a note to hang in the window, hopeful that the cellist would see it before he started playing.  

_PH1_

_Spiegel im Spiegel Pärt_

_2 PM_

And then, he waited.  He left the window open just a little, on the off chance that the cellist didn’t see the note. But just before two, when a knock sounded on the door, Magnus nearly jumped out of his skin, hurrying to answer.  On the other side stood his cellist, a little taller than Magnus, cello in hand. “Um, hi,” he smiled and Magnus fell in love.

“Hello, darling.  Please come in.” The man stepped inside looking lost until his eyes fell on the piano and he visibly relaxed.  “My name is Magnus,” he introduced himself. “And you are?”

“Alexander.  I mean, Alec Lightwood.”  

Realizing just how nervous the cellist, _Alexander_ was, Magnus gestured to the piano.  “Shall we play? Do you know the piece?”

“One of my favorites,” he admitted, already setting up his cello and stand.  

They set up so they could see one another and once ready, they slipped into the piece like every other song they’d played together.  But this one was different. Neither even looked at the score, their eyes locked on one another except for when a particular phrase had them close their eyes as they lost themselves in the music.  While Alec’s music was the most beautiful thing Magnus ever heard, Alec playing his cello was the most beautiful thing he’d ever seen. The way he moved with the music, his hand moving up and down the neck of his instrument.  He was intoxicating and Magnus wanted more.

They played and they played, for over ten minutes it was just the two of them, the music and the energy that crackled between them.  And when the song came to an end, neither said anything for several long minutes, not wanting to break the spell they’d weaved together.  

“Would you like to go get a drink sometime?” Magnus finally asked once he found his voice again.  

Alec’s answering smile made Magnus’ stomach flop and he nodded.  “I’d love that. But...can we play that again?”

“Absolutely, darling.”  

And once more, the two of them lost themselves to each other and their music.

**Author's Note:**

> Songs from this piece:  
> [Clair de Lune](https://www.youtube.com/watch?v=vG-vmVrHOGE)  
> [The Swan](https://www.youtube.com/watch?v=eo2y23NVOg8)  
> [Stay With Me (Song Alec played with Jace)](https://www.youtube.com/watch?v=B22eZY1PESY)  
> [Hallelueh (Song Alec played with Jace, pt 2)](https://www.youtube.com/watch?v=e1C9kpMV2e8&list=PLXdaORVZTx4ArBejoUyAYdtMy5VtDf5C9&index=25)  
> [Spiegel im Spiegel](https://www.youtube.com/watch?v=FZe3mXlnfNc)
> 
> Come yell at me on tumblr at [brooklynxmagic](http://brooklynxmagic.tumblr.com) or [astudyinfic](http://astudyinfic.tumblr.com)


End file.
